Recently, there has been significant interest in molecular probes as the vehicle for detection of biomarkers as tools for research in molecular biology as well as for diagnostics of various diseases and conditions. The molecular probe may be a conjugate molecule of an interrogatory component for interaction with the analyte and a detectable component, such as a fluorescent label, that allows monitoring and/or detection.
Antibody-drug conjugates (ADCs) are another emerging class of compounds generating significant interest. ADCs are typically designed as a targeted therapy, for example, for the cancers. ADCs are conjugate compounds having an antibody (e.g., a whole mAb or an antibody fragment) covalently linked to a biological active component (e.g., a cytotoxic payload or drug), often via a stable but releasable linkage.
Another strategy in improving therapeutics is PEGylation, a process of covalently attachment of polyethylene glycol (PEG) polymer chains to a molecular probe, a drug or therapeutic protein or antibody. Reported benefits of PEGylation include masking of an agent to reduce immunogenicity and antigenicity, and prolonging an agent's circulatory time by reducing renal clearance, as well as providing water solubility to hydrophobic drugs and proteins.
While these above-mentioned strategies have drawn increasing interests, a number of outstanding issues and limitations remain that affect the scope and effectiveness in actual applications. Novel approaches are desired that afford novel compounds, compositions and methodologies with expanded functionalities and utilities.